Here's a link to where this came from
http://tinyurl.com/yawgyek
As far as what to do I have no clue, I feed my plants tap water and I don't even really let it sit out like they suggest doing. GOOD LUCK!
City water is filtered for the safety of humans; however, plants do not agree with many of the chemicals used in that process. Some plants are more sensitive than others; palms, spider plants and dracaenas are quite sensitive to fluoride. The fluoride acceptable in tap water is still more than plants can handle. Additionally, tap water can also contain salts for softening which can be harmful. A build-up of a white film crust forms on soil, this is a sign water has too much sodium- a nutrient plants despise. Finally, water that has the wrong pH level can damage plants. To combat tap water problems, installing a filtered system at home would be ideal; but, letting water sit out for 24-hours before watering, experts say, can also remove harmful chemicals. It is also said that rain water is great to use, which can be done by setting out buckets to collect precipitation. According to the Water Quality Association, distilled or reverse-osmosis filtered water is the best for watering house plants. No matter where the safe water comes from, it should be room temperature when watering.